This invention relates to an ultrasonic tool, including an apparatus coupling one end of an elongate sonotrode to the mechanical amplifier portion of an ultrasonic tool or instrument.
In ultrasonic tools and processing instruments of the type including a vibrational transducer, a mechanical amplifier or booster element coupled to the transducer for enhancing the amplitude of its vibrational oscillations, and an elongate sonotrode or "mason's horn" coupled to an output end of the amplifier element, one prior art arrangement for effecting the latter coupling simply amounts to threading one end of the sonotrode and screwing it into a similarly threaded bore in the end of the amplifier element. An extremely precise axial alignment of the coupled components is essential in devices of this type, however, and such alignment is thwarted in the construction just described since the angular orientation of the screwed in sonotrode relative to the end of the amplifier element is a function of thread wear, the amount of abrasive material introduced between the abutting surfaces of the two components, etc. Precise axial alignment is thus difficult to achieve in an assembly arrangement of this type, which entails a tedious adjustment process following the installation of each new sonotrode.
In another prior art design a flanged end of the sonotrode is attached to the externally threaded output end of the amplifier using a centrally apertured screw cap through which the sonotrode body extends. This allows the same relative angular orientation between the two components to be maintained as the sonotrode itself is not rotated, but axial offsets are still a problem and the relatively large mass of the screw cap absorbs vibratory energy and thus reduces the useful output amplitude of the device.
In ultrasonic instruments of this type the sonotrodes are subject to heavy wear and deterioration, and must be frequently replaced. The known mounting arrangements for such sonotrodes do not enable their rapid exchange with precise axial alignment and an effective energy propagation.